The mission of the Tea Chemistry and Analysis (TC&R) Core is to facilitate the research activities of the four Projects of this Program Project by providing well-characterized tea preparations and purified tea constituents/metabolites and performing chemical analyses that are required by the four Projects. The specific aims are as follows: 1. Procure tea preparations and purify tea constituents. The caffeine and tea polyphenol contents in the tea preparations will be analyzed at the time of use. The stability of these compounds in solutions under experimental condition will be determined. 2. Determine plasma/tissue levels of catechins, caffeine, and their metabolites in selected samples from Projects 1 and 2. 3. Analyze the fatty acid compositions of fat pad samples from Projects 1 and 2. 4. Synthesize catechin metabolites and radio labeled compounds. These include O-methyl, glucuronide, and sulfate derivatives of EGCG and EGC, catechin ring fission metabolites M4 and M6, and theasinesins.